Web tension regulating apparatus

ABSTRACT

A web handling apparatus is adapted to move web material in forward and reverse directions and under varying degrees of web tension. In such apparatus, a web friction drive is actuatable to assume an operative mode for feeding web material, therefrom, in the forward direction toward a web drawing mechanism and at a rate in excess of that at which the drawing mechanism can draw the same material forward. The web friction drive normally assumes an idle mode in which the friction drive does not exert a web feeding affect on web material moving in the forward or reverse directions. A web tension sensing mechanism connects with the web friction drive, for actuating the friction drive to assume the operative mode in response to sensing a given tension in web material which is moving in the forward direction from the friction drive to the web drawing mechanism, and allows the friction drive to assume the idle mode after tension in the same material has eased or slackened. However, the web tension sensing mechanism and web friction drive remain disconnected as web material is moved in the reverse direction. In this way, the web tension sensing mechanism cannot actuate the web friction drive to assume the idle mode during movement of web material in the reverse direction.

United States Patent [191 Martin WEB TENSION REGULATING APPARATUS [75]Inventor: -William A. Martin, Fairport, NY.

[73] Assignee: Eastman Kodak Company,

Rochester, NY.

[22] Filed: Apr. 5, 1973 [21] Appl. No.: 348,446

[52] US. Cl 226/36, 226/195, 242/189, 352/124 [51] Int. Cl B65h 23/16[58] Field of Search. 226/36, 44, 49, 108, 115, 183, 226/195; 242/189;352/124, 159

[56] v References Cited UNITED STATES PATENTS 1,786,917 12/1930Oehmichen 242/189 3,065,890 1l/1962 Fox 226/36 3,460,889 8/1969 Wilhal'm352/124 3,240,550

3/1966 Mitchell et a1 242/189 X Primary Examiner-Allen NI KnowlesAssistant Examiner-Gene A. Church 71 ABSTRACT A web handling apparatusis adapted to move web ma- [1 11 3,794,231 [4 1 Feb. 26,1974

terial in forward and reverse directions and under varying degrees ofweb tension. In such apparatus, a web friction drive is actuatable toassume an operative mode for feeding web material, therefrom, in theforward direction toward a web drawing mechanism and at a rate in excessof that at which the drawing mechanism can draw the same materialforward. The web friction drive normally assumes an idle mode in whichthe friction drive does not exert a web feeding affect on web materialmoving in the forward or reverse directions. A web tension sensingmechanism connects with the web friction drive, for actuating thefriction drive to assume the operative mode in response to sensing agiven tension in web material which is moving in the forward directionfrom the friction drive to the web drawing mechanism, and allows thefriction drive to assume the idle mode after tension in. the samematerial has eased or slackened. However, the web tension sensingmechanism and web friction drive remain disconnected as web material ismoved in the reverse direction. In this way, the web tension sensingmechanism cann'ot actuate the web friction drive to assume the idle modeduring movement of web material in the reverse direction.

i 19 Claims, 3 Drawing Figures PATENTEU P5525574 3.. 794.231

' sum 1 [IF 2 PATENTED H1526 I974 SHED 2 0F 2 FIG. 3

1 WEB TENSION REGULATING APPARATUS CROSS REFERENCE TO RELATEDAPPLICATION TION PICTURE PROJECTOR APPARATUS and filed in the names ofWilliam A. Martin and John O. St Clair II on Oct. 5, I970.

BACKGROUND OF THE INVENTION 1. Field of the Invention The presentinvention relates to a web tension regulating apparatus for regulatingweb tension in advance of a web drawing mechanism, such as a web take-updevice or a capstan andpressure roller assembly. More particularly, theinvention relates to a film projector in which film tension regulatingapparatus regulates tension in film moving in a forward direction tofilm advancing mechanism.

2. Description of the Prior Art In many different kinds of web handlingapparatus having some mechanism for drawing a web at a known rate, it isdesirable or necessary to regulate tension in the web in advance ofsuch, mechanism. A specific example of this apparatus is that involvingthe intermittent movement of the web past a given location, such as amotion picture projector, wherein a film strip is intermittently movedpast a projection gate.

One means for regulating web tension in advance of the web drawingmechanism, in the foregoing apparatus, is a loop control arrangement formaintaining a web loop in advance of the drawing mechanism. Such webloop control arrangements have been devised heretofore and, by way ofexample, are disclosed in U.S. Pat. Nos. l,958,l52 and 2,735,677,patented respectively May 8, 1934 and Feb. 21, 1956, and commonlyassigned copending U.S. patent application Ser. No. 77,959 more fullyreferenced hereinbefore. Generally, the known web loop controlarrangements make use of variations in the size of the web loop to ceaseand scribed above.

resume operation of a web friction drive at .the en- I nism. In order toregulate the size of the web loop, and

preferably to maintain a substantially constant size loop, theperipheral speed of the driven roller is sufficiently fast to feed theweb into the loop at a rate exceeding that at which the web isdrawn'from the loop, and the pressure roller is movable away from thedriven rollerto allow slippage between the web and the driven roller fordecreasing the loop size. A web guide lever on which the pressure rolleris rotatably mounted, rides of floats on the web loop, permitting thepressureroller to press the web against the driven roller during thetime that the web'loop is below or at a given size, and moves thepressure roller away from the driven roller should the web loop exceedthe given size.

It will be appreciated that the particular web loop control arrangement,just described, relies on the stiffness or rigidity of the web loop todiscontinue the driving relation between the driven and pressurerollers. Accordingly, in this instance, a web an insufiicient' measureof stiffness cannot be used.

In applications where the web does not have a requisite measure ofstiffness necessary for use with a web loop control arrangement, othermeans must be found for regulating web tension in advance of the Webdrawing mechanism. One embodiment of such other means appears to bedisclosed in U.S. Pat. No. 2,800,832, patented July 30, 1957. In thisembodiment, successive portions of a web are fed into the nip defined bya pressure roller and a driven roller which, in turn, feed the webforward to a web drawing mechanism. Here, no intervening web loop existsbetween the driven and pressure rollers and the web drawing mechanism.Rather, the pressure roller and a tension sensing roller areinterconnected by a lever for synchronous pivotal movement of suchrollers in the same direction about a common intermediate pivot point.Therefore, an increase in web tension causes the tension sensing rollerto actuate the pressure roller to press the web against the drivenroller, and a decrease -or lack of web tension permits the pressureroller to move away from the driven roller such that slippage occursbetween the web and the driven roller. While this web tension regulatingmeans may perform satisfactorily during forward movement of the web frombetween the driven and pressure rollers to the web take-up mechanism,such means appears to phohibit reverse or rewind movement of the web,because the increased web tension normally occurring in high speed webrewind will cause the tension sensing roller to induce the pressureroller to press the web againstthe driven roller so as to inhibit ordefeat web rewind. I

SUMMARY OF THE INVENTION It is therefore a primary object of the presentinvention to provide a web tension regulating apparatus which isimproved over the prior art examples de- It is another object of thepresent invention to provide a web tension regulating apparatus whichregulates tension in a web moving in a forward direction to a webdrawing mechanism, and which allows the web to be moved in a reversedirection'from the drawing mechanism.

A further object of the present invention is to provide a webtension-regulating apparatus which can handle a web not having therequisite measure of stiffness necessary for use with a web loop controlarrangement.

In accordance with the present invention there is dis closed, in detailhereinafter, a web handling apparatus of the kind for moving webmaterial in forward and reverse directions and under varying degrees ofweb tension. In such apparatus, a web friction drive is actuat- .terial,therefrom, in theforward direction to a web drawing mechanism and ata'rate in excess of that at which the drawing mechanism can draw thesame material forward. The web friction drive normally assumes an idlemode in which the friction drive does not exert a web feeding affect onweb material moving in the forward or reverse directions. A web tensionsensing mechanism connects the web friction drive, for actuating thefriction drive to assume the operative mode in response to sensing agiven tension in web material which is moving in the forward directionfrom'the friction drive to the web drawing mechanism, and allows thefriction drive to assume the'idle mode after tension in the samematerial has eased or slackened. However,

the web tension sensing mechanism and the web friction drive remaindisconnected as web material is moved in the reverse direction. In thisway, the web tension sensing mechanism cannot actuate the web frictiondrive to assume the idle during movement of web material in the reversedirection.

BRIEF DESCRIPTION OF THE DRAWINGS The above-mentioned and other featuresand objects of the present invention and the manner of obtaining themwill become more apparent by reference to the following detaileddescription of a preferred embodiment of such invention taken inconjunction with the accompanying drawings, wherein:

FIG. 1 is a plan view of a web tension regulating apparatus inaccordance with a preferred embodiment of the present invention, andshows the operation of such paratus, showing the operation of suchapparatus during reverse movement or rewinding of web material from theweb take-up reel to the web supply reel.

DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of theinvention will be described hereinafter for use in a motion pictureprojection device. However, because motion picture projection devicesare well known in the art, the present description will be directed inparticular only to those components of such a projection device whichcooper-.

ate directly with the invention, components of the projection device notspecifically shown or described are understood to be selectable fromthose known in the art. Moreover, it will be appreciated from thedescription thereinafter'that the invention is suitable for use withother photographic devices, such as a camera, and, in general, can beused with various devices involving the feeding of web material.

Referring now to the drawings and in particular to FIG. 1, there isshown certain components of a motion picture projection device 1 havingan enclosure 2 from which a pair of spaced spindles 3 and 4 project, torotatably support thereo na film supply reel 5 and a film take-up reel6. These spindles 3 and 4 operate in conjunction respectively withone-way drive clutch or other appropriate mechanisms 7 and 8 forallowing free rotation of an individual spindle during the time suchspindle is rotating in a direction for unwinding or paying-out a filmstrip F from the reel thereon, and coupling the spindle to a power drive9 for rotating the spindle in a direction for winding or taking-up thefilm, strip onto the reel. Specifically, as shown in FIG. 1, the spindle4 is driven in a winding direction 10 by means of the power drive 9 anda tendency drive clutch 8 for winding the film strip F about a core orhub member 11 of the reel 6, while the spindle 3 and the reel 5 freelyrotate in the unwinding direction 12. Moreover, as shown in FIG. 3, tofacilitate rewinding of the film strip F about a core or hub member 13of the reel 5, the spindle 3 is driven in a winding direction 14, at ahigh rate of speed, by means of the power drive 9 and a direct drive 7,while the spindle 4 and the reel 6 freely rotate in an unwindingdirection 15. Sincesuch direct drive 7, tendency drive 8 and power drive9 for achieving the foregoing functions are well known in the art,further description thereof is considered unnecessary for anunderstanding of the invention.

Initially, as shown in FIG. 1,-a film feeding or threading mechanism(not shown, but fully disclosed in commonly assigned copending US patentapplication Ser. No. 77,959) delivers a free leading end portionL of thefilm strip F from the supply reel 5 into a nip 16 jointly defined by adriven roller or capstan l7 and a pressure roller 18. After passing frombetween the driven and pressure rollers 17 and 18, the leading film endportion L is fed by such rollers in a forward direction 19 along astationary guide track 20, through a projection gate 21, and into a nip22 jointly defined by a driven roller or capstan 23 and a pressureroller 24. A flying spot scanner (not shown) can be provided in the areaof the projection gate 21 for scanning images on the film strip. F andobtaining an electronic signal from such scanned images which may, forexample, be furnished to a television receiver or to a televisioncamera. Alternatively, a suitable rotating prism mechanism and lightsource (not shown) can be provided in the area of the projection gate 21for projecting images on the film strip F in a conventional manner. Fromthe guide track 20, the

driven and pressure rollers 23 and 24 feed the leading film end portionL'into a first guide shoe 25, which is pivotally mounted for movementabout a shaft 26 of a guide roller 27 on such shoe. Immediately afterexiting from the first guide shoe 25, the leading film end portion Lenters a second guide shoe 28 which is pivotally mounted for movementabout a shaft 29 of a guide roller 30 on this shoe. Finally, afterexiting from the second guide shoev 28, the leading film end portion Lmoves onto the core member 11 of the take-up reel 6 and is snubbedthereto by any well known snubbing or self-threading mechanism (notshown). At this time, of course, the tendency drive 8- is coupled to thepower drive 9 for rotating the take-up reel 6 in the winding directionl0, and the direct drive 7 is uncoupled from the power drive forallowing the supply reel 5- to rotate in the unwinding direction 12.

Previous to deliverypf the leading film end portion L into the nip 16 ofthe driven and pressure rollers 17 and 18, and in response to theappliclation of electrical power (source not shown) to the projectiondevice 1', a normally closed switch 31' actuates or energizes a solenoid32 which is connected by a helical tension spring 33 to a pressureroller support arm 34; This arm 34, on which the pressureroller 18 isrotatably mounted, normally locates such pressure rollerin an-idleorfilm guiding position in which the pressure roller is sufficientlyspaced from the driven roller 17 to permit generally free movement ofthe film strip F therebetween. However, the arm 34 is pivotally mountedfor movement about a pivot-pin 35, for swinging the pressure roller 18from the idle position to an operative or film feeding position in whichsuch pressure roller presses successive portions of the film strip Fagainst the driven roller 17, for feeding the film strip in the forwarddirection 19 along the stationary guide track 20. Accordingly,energization of the solenoid 32 serves to move the pressure roller 18from the idle position to the operative position; whereupon, the leadingfilm end portion L is fed from the driven and pressure rollers 17 and 18port arm 34, during the time that the solenoid 32 is ene'rgiz'ed, mustbe sufficient to overcome this urging force which the film strip Fexerts on the pressure roller 18. Conversely, during the time that thesolenoid 32 is not energized, the pulling force of the spring 33 must benonexistent or insignificant so asnot to interfere with the normallocatiOn of the pressure roller 18 in the idle position. I

When the leading film end portion L is threaded onto the core member 11of the take-up reel 6, the resulting increase of longitudinal tension inthat reach or section of the film strip F extending from between thedriven and pressure rollers 23 and 24 to such core member causes thisfilm reach to foreshorten in length (from the guide roller 27 to theguide roller 30) and apply a lateral force against a guide roller 36 onthe first guide shoe 25. This, in turn, causes the first shoe 25 topivot counterclockwise about the shaft 26, as depicted in FIG. 1, andagainst the urging ofa helical tension spring 37. In response to suchpivotal movement of the first guide shoe 25, afinger member 38 extendingtherefrom, moves a flexibly movable contact 39 of the switch 31 awayfrom a stationary contact40 of the switch, opening the switch todeenergize the solenoid 32. When the solenid 32.is deenergized, thepressure roller 18 returns to the idle position, since such roller is nolonger held in theoperative position.

Ascan be seen on viewing FIGS. 1-3, a guide roller 41 is locatedopposite and inside of a curve or bend 42 in the stationary guide tracksuch that a sufficient longitudinal tensioning of that reach of the filmstrip F extending along the guide track between the driven and pressurerollers 17 and 18 and the driven-and pressure rollers 23 and 24, causessuch film reach to foreshorten in length and apply a lateral forceagainstthis guide roller. A guide'roller support arm 43, on which theguide roller 41 is rotatably mounted, serves to cooperate with thestationary guide track 20 for guiding the film strip F between suchguide roller and the driven and pressure rollers 17-and- 18. This'arm 43is pivotally mounted for movement with the guide roller 41 about a pivotpin 44. Accordingly, as the filmforce applied against the guide roller41 increases due to increased longitudinal tensioning of the film stripF at the bend 42 in the guide track 20, the guide roller 41 is movedwith the guide roller support arm 43 from a first film guiding positionshown in FIG. 1, to a second film guding position shown in FIG. 2,-andto a 'third film guiding position shown in FIG. 3. A helical compressionspring 45 urges the guide roller or (as referred to hereinafter) theten- A connectingfinger 46 is pivotally mounted on the pivot pin 47. Ahelical compression spring 48 urges the connecting finger 46 to a readyposition, shown in FIG. 1, and in which a stop 49 on such finger abutsagainst a raised edge 50 on the arm 43. A motiontransmltting lever 51has flexibly movable, opposite end portions 52 and 53 and a fulcrum orpivot point 54 located therebetween. The lever fulcrum 54 is disposedwith respect to the pressure roller support arm 34and the connectingfinger 46 such thatthe lever end portions 52 and 53 and the finger andarm are movable respectively into motion transmitting relation, to causethe movement of the pressure roller 18 from the idle position to theoperative position as the tension sensing roller 41 is moved from thefirst guiding position to the second guiding position. Specifically, ascan be' seen from a comparison of FIGS. 1 and 2, during movement of thetension sensing roller 41 with the arm 43 from the first guidingposition to the second guiding position, the connecting finger 46 movestherewith, and an engageable piece 55 on the finger engages the leverend portion 52 so as to swing the lever 51 about the fulcrum 54 andforce the lever end portion 53 further against an extending member 56 ofthe pressure roller support arm 54. When the connecting finger 46 is inthis connecting position, i.e.,

in engagement with the lever end portion 52, continued movement of thetension sensing roller 41 from the first guiding position to the secondguiding position causes the lever 51 to swing about the fulcrum 54,moving the pressure roller 18 from the idle position to the operativeposition. Subsequently, of course, should the tension sensing roller 41.return from the second guiding position to the first guiding position,the connecting finger 46 will separate from the lever end portion 52,allowing the pressure roller 18 to return from the operative position tothe idle position. v

It is apparent from the foregoing description that should thelongitudinal tension fluctuate, i.e., increase and decrease, in thoseportions of the film strip F moving in the forward direction 19individually about the tension sensing roller 41, then the driven andpressure rollers 17 and 18 will function as an intermittent film drive(in that such pressure. roller and the tension sensing roller move tothe operative and second guiding positions, respectively, in response toincrease film tensioning and move to the idle and first guidingpositions, respectively, in response to decreased film tensioning). Thisfluctuation in film tension at the tension sensing roller 41 can becaused, or example, by variations in the flange member spacing (notshown),'from one film convolution to the next, on the supply reel 5 andbythe resulting fluctuation in film drag as the film strip F is drawn inthe forward direction 19 from the supply reel. If the driven andpressure rollers 17 and 18 were to function as a continuous (rather thanan intermittent) film drive, as in the case of the driven and pressurerollers 23 and 24, then any dissimilarity in the respective diameters ofsuch driven rollers would produce different peripheral speeds ofrotation of these rollers. This variation in roller speed would producedifferent-rates of film drive, causing excessive film tensioning or filmslackening along the stationary guide track 20. Thus, in accordance withthe invention, the driven roller 17 is rotated by a power drive 57 withsufficient peripheral speed such as that the pressure roller 18, inthe-operative position, cooperates with this driven roller to feed cessof that at whichthe pressure and driven rollers 23 and 24 can draw oradvance the film strip from the guide track. The power drive 57 forrotating the driven roller 17, as well as a power drive 58 for rotatingthe driven roller 23, are actuated or energized in response to theapplication of electrical power (source not shown) to the projectiondevice 1.

During movement of thefilrn strip F in the forward direction 19 alongthe stationary guide track 20, the tension sensing roller 41 serves as ameans for sensing the demand forfilm at the projection gate 21 and atthe driven and pressure rollers 23 and 24. This demand, of

course, is measured by fluctuations in film tension atthe tensionsensing roller 41. Moreover, as stated above and as can be seen onviewing FIGS. 1 and 2, in response to increased film-tension at theroller 41, such roller moves from the first guiding position to thesecond guiding position, causing the pressure roller 18 to move from theidle position to the operative position. Immediately thereafter, thefilm strip F is fed into the guide track at a rate in excess of that atwhich the film strip is drawn from the guide track. As soon as filmtension at the tension sensing roller 41 has decreased a given amount,such roller returns to the first guiding position and the pressure,roller 18, in turn, returns to the idle position. Movementof the tensionsensing roller 41 between the first and second guiding positions, andmovement of the pressure roller 18 between the idle and operativepositions, occurs repeatedly during the time that the film strip F ismoving in the forward direction 19 along the-guide track 20, with theresultthat the tension fluctuations in such film strip are regulated andmaintained between relatively narrow limits. As can be realized from acomparison of FIGS. 1 and 3, after the leading film end portion L issnubbed to the.

core member 11 of the take-up reel 6, and during the time that the filmstrip F is winding onto such reel, the

second guide shoe 28 pivots about the shaft 29 against I the urging ofahelical compression spring 59, and the first guide shoe remainsgenerally stationary to hold the switch 31 open. Since a trailing endportion (not shown) of the film strip F is anchored to the core member13 of the supply reel 5, after the last convolution of the film strip isunwound from the supply reel, the longitudinal tension in that reach ofthe film strip extending from the supply core to the driven andpressurerollers 23 and 24 will suddenly increase. Upon this occurrence,the film force applied agains the tension sensing roller 41, at the bend42 in the stationary guide track-20, undergoes a corresponding increaseand the tension sensing roller is moved with the tension sensing rollersupport arm 43 from the first or second guiding positions, shownrespectively in FIGS. 1 and 2, to the third guiding position, shown inFIG. 3. As shown in FIG. 3, this movement of the roller 41 and the arm43 to the third guiding position causes the closure ofa normally openswitch 60. Specifically, a shaft 61 of the tension sensing roller 41moves a flexibly movable contact 62 of the switch 60 into abutmentagainst a stationary contact 63 of such switch. Closure of the switch 60operates to energize or actuate a solenoid 64 which, thereupon, pivots aseparating lever 65 clockwise, as viewed in FIG. 3, about a fulcrum orpivot point 66 and against the urging of a helical tension spring 67.This pivoting of the separating lever 65, from an inactive positionshown in FIGS. 1 and 2 to a separating position shown in FIG. 3, movesthe connecting finger 46 against the urging of the spring 48 from theready position shown in FIG. 1, or from the connecting position shown inFIG. 3. As is apparent from FIG. 3, in the disconnecting position, theconnecting finger 46 is prevented from engaging with the end portion 52of the motion transmitting lever 51. The connecting finger 46 is held inthe disconnecting position by the separating lever 65 as long as theswitch remains closed. In this way, the tension sensing roller 41 cannotcause the pressure roller 18 to move to the operative position.

Closing of the switch 60 further operates, by well knownelectromechanical means, to uncouple the tendency drive clutch 8 and thepower drive 9, allowing free rotation of the take-up reel 6, and tocouple the di rect drive 7 and the power drive for rotating the supplyreel 5, at a high rate of speed, in the winding direction 14 shown inFIG. 3. Such winding rotation of the supply reel 5 causes the film stripF to be wound thereon, and unwound from the take-up reel 6. During thisoccurrence, of course, the film strip F is drawn in a reverse direction68 along the stationary guide track 20, and is longitudinally tensionedalong the guide track to retain the tension sensing roller 41 in thethird guiding position and keep the switch 60 closed.

A carriage 69, on which the pressure roller 24. is rotatably mounted,enables such roller to be moved toward and away from the driven roller23. since that portion of the film strip F moving in the forwarddirection 19 between the-driven and pressurerollers 23 and 24 islongitudinally tensioned and, in addition, is partially wrapped aboutthepressure roller, this film portion tends to apply a lateral forceagainst the pressure roller for urging such roller away from the drivenroller. However, a helical compression spring 70 urges the pressureroller 24 to press the film strip F against the driven roller 23 with anurging force, which is greater than the film force applied against thepressure roller as the film strip moves in the forward direction 19,-andwhich is less thanthe film force applied against the pressure roller asthe film strip moves in the reverse direction, 68. Accordingly, as shownin FIG. 1, the pressure roller 24 presses the film strip F against thedriven roller 23 to draw or advance the film strip in the forwarddirection 19 along the stationary guide track 20 and to feed the filmstrip in the same direction to the take-up reel 6. On the other hand, asshown in FIG. 3, during the time that the film strip F moves in thereverse direction 68, the pressure roller 24 is spaced from the drivenroller 23 so as not to exert any film feeding affect on such movingstrip.

As can be seen in FIGS. 1 and 3, a helical tension I spring 71 maintainsthe end portion 53 of the motion transmitting lever 51 in contact withthe extended member 56 of the pressure roller support arm 34 during thetime such arm and the pressure roller 18 are in the idle position.However, this spring 71 does not have a s'ufficient range to interferewith the arm 34 and the roller 18 normally assuming the idle position.There fore, after the solenoid 64 is deenergized, the lever 51, the arm34 with the roller 18, and the connecting finger 46 return from therelative locations shownin FIG. 3

- to those shown in FIG. 1.

tions can be effected within the spirit and scope of the invention. Iclaim:.

1 In a web handling apparatus of the kind for moving web material inforward and reverse directions along a web path and under varyingdegrees of web tension, the combination comprising:

web advancing means for advancing web material in the forward directionalong the web path; web feeding means actuatable to assume a feedingmode for feeding web material in the forward direction along the webpath toward said web advancing means, at a rate in excess of that atwhich said advancing means. can advance web material, and normallyassuming a non-feeding mode in which said feeding meansdoes not feed webmaterial; web tension sensing means for actuating said web feeding meansto assume the feeding mode in response to sensing a given tension in webmaterial moving in the forwarddirection along the web path between saidweb advancing means and said feeding means, and for allowing saidfeeding means to assume the non-feeding mode after tension in the samematerial has eased; and means for preventing said web tension sensing'means from actuating said web feeding means to assume the feeding modeas web material is moved in the reverse direction along the web path,thereby to permit said web feeding means to remain in the' rection alongthe web path toward said web advancing means, at a rate in excess ofthat at which said advancing means can advance web material, andnormally assuming a non-feeding mode in which saidfeeding means does notfeed web material;

web tension sensing means for sensing tension in web material moving inthe forward direction along the webpath between said web advancing meansand said web feeding means;

means for connecting said web feeding means and saidweb tension sensingmeans for actuating said feeding means to assume the feeding mode, inresponse to said tension sensing means sensing a given tension in webmaterial moving in the forward direction along the web path between saidfeeding means and said web advancing means, and for allowing saidfeeding means to assume the nonfeeding mode after tension in the samematerial has eased; and

means cooperating with said connecting means for preventing a connectionbetween said web feeding 10 means and said web tension sensing means asweb material is moved in the reverse direction along the web path,thereby to permit said feeding means to remain in the non-feeding mode;

3. In a web handling apparatus of the kind for moving web material inforward and reverse directions along a web path and under varyingdegrees of web tension, the combination comprising:

means for advancing web material in the forward direction along thewebpath;

a driven member against which successive portions of web material can bepressed for feeding web mate rial in the forward direction along the webpath toward said web advancing means; v

a pressure member;

means supporting said pressure member for movement to an operativeposition in which said pressure member is disposed to cooperate withsaid driven member for feeding web material by pressing successiveportions of web material against said driven member, and normallylocating said pressure-member in an idle position in which said pressuremember is disposed with'respect to said driven member for permittinggenerally free movement of web material therebetween; 1

means for driving said driven member with sufficient speed such thatsaid pressure member, in the operative position, cooperates with saiddriven member at which said web advancing means can advance webmaterial, so as 'to ease'tension in web material moving in the forwarddirection along the web path between said driven and pressure membersand said advancing means;

means for sensing tension in web material moving in the forwarddirection along the web path between said driven and pressure membersand said web advancing means;

means for connecting said pressure member and said web tension sensingmeans for moving said pressure member from the idle position to theoperative position, in response to sensing a given tension in webmaterial moving in the forward direction along the web path between saiddriven and pressure members and said web advancing means, and forallowing said pressure member to return to the idle position aftertension in the same material has I eased; and means cooperating withsaid connecting means for preventing a connection between said pressuremember and said web tension sensing means as web material. is moved inthe reverse direction along the web path, thereby to permit saidpressure member to remain in the idle position. v 4. The combination asrecited in claim 3, wherein said web advancing means initially serves toadvance a leading end portion of web material in the forward directiononto a rotatably supported core member to which the leading web endportion can be snubbed and about which web material can be wound, andwherein the combination further comprises:

means energizable for holding said pressure member in the operativeposition, and deenergizable for allowing said pressure member to returnto the idle position; and

means actuatable in response to the leading web end portion snubbing tothe core member for deenergizing said pressure member holding means.

'5. The combination as recited in claim 3, wherein said pressure memberis a pressure roller, and wherein said pressure member supporting meanssupports said pressure roller for movement .toward and away from saiddriven member respectively between the operative and idle positions andlocates said pressure roller in said web handling apparatus such thatweb material moving between said driven member and said pressure rolleris partially wrapped about said pressure roller for urging said pressureroller to move away from said driven member as tension in the samematerial increases.

6. ln a web handling apparatus of the kind for moving web material inforward and reverse directions along a' web path and under varyingdegrees of web tension, the combination comprising:

means for drawing web material in the forward direction along the webpath;

a driven member against which successive portions of webmaterial can bepressed for feeding web material in the forward direction-along theweb'path toward said web drawing means;

a pressure member;

4 means supporting said pressure member for movement to an operativeposition in which said pres- I sure member is disposed'to cooperate withsaid driven member for feeding web material by pressing successiveportions of web material against said driven member, and normallylocating said pressure member in an idle position in which said pressuremember is disposed with respect to said driven member for permittinggenerally free movement of web material therebetween;

means for driving said driven member with sufficient speed such-thatsaid pressure member, in the operative position, cooperates with saiddriven member for feeding web material at a rate in excess of that atwhich said web drawing means can draw web material, so as to easetension in web material moving in the forward direction between saiddriven and pressure members and said web drawing means;

a web guide member disposed with respect to said web drawing means andsaid driven and pressure members for guiding web material such that asufficient tcnsioning of web material moving in the forward directionbetween said driven and pressure members and said drawing means causesthe same material to foreshorten in length and apply a web force againstsaid guide member;

means supporting said web guide member for move ment from a first webguiding position to a second web guiding position in response to webmaterial applying a given force against said guide member;

means for urging said web guide member from the second web guidingposition to the first web guiding position with an urging force which isless than the given force required to move said guide member from thefirst web guiding position to the second web guiding position;

means for connecting said pressure member and said web guide member suchthat movement of said guide member from the first web guiding positionto the second web guiding position causes move- 12 ment of said pressuremember from the idle position to the operative position, and allowingsaid pressuremember to return to the idle position after tension haseased in web material moving in the forward direction between saiddriven and pressure members and said web drawingmeans; and meanscooperating with said connecting means for preventing a connectionbetween said pressure member and said web guide member as web materialis moved in the reverse direction along the web path thereby to permitsaid pressure member to remain in the idle position. 7. The combinationas recited in claim 6, wherein said web drawing means includes means forcontinuously moving web material, therepast, in the forward direction ata substantially constant rate. I

8. The combination as recited in claim 7, wherein said continuous webmoving means includes a driven roller against which successive portionsof web material can be pressed for moving web material, therepast, inthe forward direction, means for rotating said driven roller at asubstantially constant speed, a pressure roller, means. supporting saidpressure roller for movement toward and away from said driven rollerandsuch that web material moving between said driven and pressure rollersapplies a web force against said pres sure rollerfor urging saidpressure roller tomove away from said driven roller, and means forurging said pressure roller to press web material against said dri'venroller with an urging force which is greater than a web force appliedagainst said pressure roller as web material is moved in the forwarddirection between said driven and pressure rollers and which is lessthan a web force applied against said pressure roller as web material ismoved in the reverse direction between said driven and pressure rollers.

9. The combination as recited in claim 6, wherein said web drawing meansand said. driven and pressure members serve to draw web material off arotatably supported core member about which a web supply roll is woundand to which a trailing web end portion is anchored, wherein said webguide member supporting means supports said web guide member formovement from the second web guiding position to a third web guidingposition in the event that all butthe trailing web end portion is drawnoff the core member and web material moving in the forward directionbetween the core member and said web drawingmeans foreshortens in lengthand applies a' greater force against said guide member than thatrequired to move said guide member from the first web guiding positionto the second web guiding position, wherein said connecting meansincludes motion transmitting meansmovable to connecting anddisconnecting positions respectively in which said motion transmittingmeans connects and cannot connect said pressure and web guide members inmotion transmitting relation, and wherein said connection preventingmeans includes means actuatable in response to movement of said webguide member to the third web guiding position for moving said motiontransmitting means to'the disconnecting position.

10. The combination as recited in claim 9', further comprising:

means actuatable in response to movement of said web guide member to thethird web guiding position for initiating movement of web material inthe reverse direction along the web path.

11. The combination as recited in claim 9, wherein said pressure membersupporting means includes a pressure member support arm which ispivotally mounted for moving said pressure member toward and away fromsaid driven member respectively between the operative and idlepositions, wherein aid web guide member supporting means includes a webguide mem: ber support arm which is pivotally mounted for moving saidweb guide member between the first, second and third web guidingpositions, wherein said motion transmitting means includes a leverhaving opoosite end portions and a fulcrum located therebetween suchthat said lever end portions and said pressure and web guide membersupport arms are movable respectively into tion transmitting means tothe disconnecting position includes means forseparating one of saidlever end portions and one of said pressure and web guide member supportarms for preventing movement of said end portions and said support armsinto motion transmitting relation.

12. The combination as recited in claim 6, wherein said pressure membersupporting means includes a pressure member support arm which ispivotally mounted for moving said pressure member toward and away fromsaid driven member respectively between the operative and idlepositions, wherein said web guide member supportingmeans includes a webguide member support arm which is pivotally mounted for moving said webguide member between the first and second web guiding positions, whereinsaid connecting means includes a lever having opposite end portions anda fulcrum located therebetween such that said lever end portions andsaid pressure and web guide member support arms are movable respectivelyinto motion transmitting relation to cause movement of said pressuremember from the idle position to the operative position as said webguide member is moved from the first web guiding position to the secondweb guiding position, and wherein said connecting preventing meansincludes means for separating one of said lever end portions and one ofsaid pressure and web guide member support arms for preventing movementof said end portions and said support arms into motion transmittingrelation.

13. An improved web handling apparatus of the kind (a) wherein there isprovided a driven member against which successive portions of webmaterial can be pressed for feeding web material, (b) wherein there isprovided a pressure member normally located in anidle position in whichsaid pressure member is disposed with respect to said driven member forpermitting generally free movement of web material therebetweeen, andmovable from the idle position to an operative position in which saidpressure member is disposed to cooperate with said driven member forfeeding webmaterial by pressing successive portions of web materialagainst said driven member, (c) wherein there is provided a. web guidemember disposed with respect to said driven member and said pressuremember such that a sufficient tensioning ofweb material extendingbetween said driven and pressure members and said guide member causesthe same material to foreshorten in length and apply a web force againstsaid guide member, and movable from a first web guiding position to asecond web guiding position in response to web material applying a givenforce against said guide member, (d) wherein there is provided means forconnecting said pressure member and said web guide member such thatmovement of said guide member from the first web guiding position to thesecond web guiding position causes movement of said pressure member fromthe idle position to the operative position, and wherein the improvementcomprises:

said connecting means including a lever having opposite end portions anda fulcrum located therebetween, said lever fulcrum disposed with respectto said pressure member and said web guide member such that said leverend portions and said pressure and web guide members are movablerespectively into motion transmitting relation to cause movement of saidpressure member from the idle position to the operative position as saidweb guide member is moved from the first web guiding position to thesecond web guiding position; and

means for separating one of said lever end portions and one of saidpressure and web guide members for preventing movement of said lever endportions and said pressure and web guide members into motiontransmitting relation. 14. The improvement as recited in claim 13,wherein said connecting means further includes a connecting moved fromthe first web guiding position to the second 1 web guiding position andmovable relative'to said guide member for disengaging from theparticular one of said lever end portions, and wherein said separatingmeans includes means for disengaging said connecting member from theparticular one of said lever end portions and for holding saidconnecting member separated therefrom. I

15. The improvement as recited in claim 14, wherein another one of saidlever end portions is flexibly movable.

16. Film projection apparatus for moving film in forward and reversedirections, said apparatus comprising:

means for supporting a film supply; a film take-up; a film gate; meansdefining a path for film from said film supply supporting means throughsaid film gate to said film take-up; i I means located with respect tothe film path between said film gate and said film take-up for advancingfilm in the forward direction through said gate and along the path at afirst rate; I actuatable film feeding means located with respect to thefilm path between said film supply and said film gate, said film feedingmeans, when actuated, being effective for feeding film in the forwarddirection along the path toward said gate at a second rate greater thanthe first rate, and said film feeding means, when not actuated, beingineffective for feeding film along the path; film tension sensing meanslocated with respect to a portion of the film path between said filmfeeding ticular magnitude of tension in film in such portion of the filmpath; means for moving film in the reverse direction along the filmpath; and means for preventing said actuating means from actuating saidfilm feeding means during movement of film in the reverse directionalong the film path. 17. Film projection apparatus as recited in claim16, wherein the film path includes a plurality of bends between saidfilm supply supporting means and said film take-up, and wherein:

said film feeding means includes a driven roller located at one side ofthe film path and a pressure roller located at the other side of thepath, and a support arm mounting said pressure roller for movementtoward and away from said driven roller; I said film tension sensingmeans includes a guide roller support arm, means mounting said guideroller support arm for pivotal movement between first and secondpositions, a guide roller mounted on said guide roller support arm andmovable with said guide roller support arm between first and second filmguiding positions, said guide roller being located along the film pathat the one bend in the path and the film being contactable with saidguide roller as the film travels along the path so that said guideroller is urged from its first guiding position toward its secondguiding position in response to an increase in tension in filmcontacting said guide roller, thereby urging said guide roller supportarm from its first position toward its second position; and saidactuating means includes a motion transmitting lever, means mountingsaid lever for pivotal movement into contact with said pressure rollersupport arm of said film feeding means for effecting movement ofsaidpressure roller carried by said pressure roller support arm toward saiddriven roller, a connecting finger pivotally mounted on said guide rol-'ler support arm for movement between (1) a first position wherein aportion of said finger is positioned for engagement with said motiontransmitting lever in response to movement of said guide roller supportarm from its first position toward its second position under theinfluence of tension in film as sensed by said guide roller so that suchmovement of the guide roller support arm can effect movement of saidmotion transmitting lever to cause said pressure roller carried by saidpressure roller support arm to be moved toward said driven roller inresponse to an increase in film tension, and (2) a second positionwherein said portion of said connecting finger is located with respectto said motion transmitting lever so that said finger is ineffective tomove said motion transmitting lever or said pressure roller support armin response to movement of said guide roller support arm from its firstposition toward its second position in response to an increase in filmtension ss sensed by said guide roller.

18. Film projection apparatus as recited in claim 17,

wherein said actuating means further includes means urging said guideroller support arm and said finger toward their respective firstpositions, and said film projection apparatus further comprises aseparating lever, means mounting said separating lever for movementbetween (1) a first position wherein said separating lever is locatedwith respect to said finger for permitting movement of said finger toits first position and (2) a second position wherein said separatinglever holds said finger in its second position against said urgingmeans, and means for moving said separating lever between its first andsecond positions.

19. Film projection. apparatus as recited in claim 18, wherein saidmeans for moving said separating lever includes a spring connected to,said separating lever for urging said separating lever to its firstposition, a solenoid coupled to said separating lever and effective whenenergized to move said separating lever to its second position, andmeans for energizing said solenoid.

20. Film projection apparatus comprising:

means for supporting a film supply;

a film take-up;

a film gate located between said film supply supporting means and saidfilm take-up; means defining a path for film from said film supplysupporting means through said film gate to said film take-up, the filmpath including at least one bend;

means located along the film path between said film gate and said filmtake-up for advancing film through said gate and along the path;actuatable film feeding means located along the film path between saidfilm supply and said film gate, said film feeding means including adriven roller located at one side of the film path and a pressure rollerlocated at the other side of the path, a support arm mounting saidpressure roller for movement toward said driven roller when said filmfeeding means is actuated, and away from said driven roller when saidfeeding means is not actuated, whereby said film feeding means, whenactuated, is effective for feeding film along the film path toward saidfilm gate, and said film feeding means, when not actuated, beingineffective for feeding film along the path;

film tension sensing means located along a portion of the film pathbetween said film feeding means and said film gate for sensing tensionin film in'such portion of the path, said film tension sensing meansincluding a guide roller support arm, means mounting said guide rollersupport arm for pivotal movement between first and second'positions, aguide roller mounted on said guide roller support arm and movablewith'said guide roller support arm between firstand second'film guiding'positions,'said guide roller being located along the film path at theone bend in the path and the film being contactable with said guideroller as the film travels along the path so that said guide roller isurged from its first guiding position toward its second guiding positionin'response to an increase in tension infilm contacting said guideroller, thereby urging said guide roller support arm from its firstposition toward its second position; and means for actuating said filmfeeding means in response to said film tension sensing means sensing aparticular magnitude of tension in film in such portion of the filmpath, said actuating means inroller support arm from its first positiontoward its second position under the influence of tension in film assensed by saidguide roller so that such movement of said guide rollersupport arm can effect movement of said motion transmitting lever tocause said pressure roller carried by said pressure roller support armto be moved toward said driven roller in response to an increase filmtension.

$276330 UNTTED STATES PATENT OFFICE CERTIFICATE OF CORRECTION mm No.3,794,231 Dated February 26, 1974 InventorGi) William- A. Martin It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Col. 9, lines 10 thru 37 Cancel Claim 1 in its entirety.

Col. 13, line ll change "opoosite" to --opposite-.

Col. 14, line 61.* delete "being" and insert --assuming a feeding modein which said feeding means is--; line 65 delete "being" and insert--assuming a non-feeding mode in which said feeding means is--;

001. 15, line 3 after "means" insert --,for connecting said a filmfeeding means and said film tension sensing means--; 1 delete "film",after "feeding means" insert -to assume the feeding mode--; line 4delete "film" line 6" after "path" insert and for allowing said feedingmeans to assume the nonfeeding mode after tension in the same film haseased--; line 9" after "means" (first occurrence) insert --cooperatingwith said connecting means-; delete "said actuating means fromactuating" and insert --a connection between--; before "during" insert--and said film tension sensing means--; line 11 after "path" insertthereby to permit said feeding means to remain in the nonfeeding mode--;

line 10 CONT Page 2 mg UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent No. 3,794,231." Dated E b 2 1914 1nventgr(g) A. MartinIt is certifie dE'th'at error appears in the aboveidentified patent andthat said Letters Patent are hereby corrected as shown below:

"connecting";

Col. 15, line 38 delete "actuating" and insert line 65 delete ss" iandinsert --as--;

line 68. delete "actuating" and insert connecting".

Signed and sealed this 29th day of October 1974.

(SEAL) Attest: v

McCOY M. GIBSON JR. 0. MARSHALL DANN Arresting Officer Commissioner ofPatents STATES PATENT'OFFICE 7 CERTIFICATE OF CORRECTION Patent No.3,794,231 Dated Februarv 26, 1974 InventorQi) William A. Martin It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below: q

Col. 9, lines lQ'thru 37 Cancel Claim 1 in itsventirety.

Col. 13, line llchange opoosite to --opposite--.

Col. 14, line l-"delete "being" and insert --assuming a feeding mode inwhich said feeding means is--; line 65 delete "being" and insert"assuming a non-feeding mode in which said feeding means is;

Col. 15, line 3 after "means" insert --,for connecting said film feedingmeans and said film tension sensing means";

delete "film", after "feeding means" insert --to assume the feedingmode; line 4 -'delete "film" line 6' after "path" insert and forallowing said feeding means to assume the nonfeeding mode after tensionin the same film has eased--; line 9 after "means" (first occurrence)insert --cooperating with said connecting means--;

- delete "said actuating means from actuating" I and insert --aconnection between"; line 10 before "during" insert --and said filmtension sensing means"; line 11 after "path" insert thereby to permitsaid feeding means to remain in the nonfeeding mode";

CON'T Page 2" I 3 UMTED STATES PATENT OFFICE I CERTIFICATE OF CORRECTIONI Dated .E h 2 6 Q 1914 Patent No. 3 794 231 Inventor) -a A- Martinppears in the above-ridentified patent It is certified that error ahereby corrected as shown below:

and that said Letters Patent are Col. 15, line 3 8 delete "actuating"and insert "connecting";

line 65 delete "es" :and insert --as--;

line 68. delete "actuating" and insert -connecting--.

Signed and sealed this 29th day of October 1974.

(SEAL) Q Attest: f

MCCOY M, GIBSON JR. 0. MARSHALL DANN Commissioner of Patents AttestingOfficer

1. In a web handling apparatus of the kind for moving web material inforward and reverse directions along a web path and under varyingdegrees of web tension, the combination comprising: web advancing meansfor advancing web material in the forward direction along the web path;web feeding means actuatable to assume a feeding mode for feeding webmaterial in the forward direction along the web path toward said webadvancing means, at a rate in excess of that at which said advancingmeans can advance web material, and normally assuming a non-feeding modein which said feeding means does not feed web material; web tensionsensing means for sensing tension in web material moving in the forwarddirection along the web path between said web advancing means and saidweb feeding means; means for connecting said web feeding means and saidweb tension sensing means for actuating said feeding means to assume thefeeding mode, in response to said tension sensing means sensing a giventension in web material moving in the forward direction along the webpath between said feeding means and said web advancing means, and forallowing said feeding means to assume the non-feeding mode after tensionin the same material has eased; and means cooperating with saidconnecting means for preventing a connection between said web feedingmeans and said web tension sensing means as web material is moved in thereverse direction along the web path, thereby to permit said feedingmeans to remAin in the non-feeding mode.
 2. In a web handling apparatusof the kind for moving web material in forward and reverse directionsalong a web path and under varying degrees of web tension, thecombination comprising: means for advancing web material in the forwarddirection along the web path; a driven member against which successiveportions of web material can be pressed for feeding web material in theforward direction along the web path toward said web advancing means; apressure member; means supporting said pressure member for movement toan operative position in which said pressure member is disposed tocooperate with said driven member for feeding web material by pressingsuccessive portions of web material against said driven member, andnormally locating said pressure member in an idle position in which saidpressure member is disposed with respect to said driven member forpermitting generally free movement of web material therebetween; meansfor driving said driven member with sufficient speed such that saidpressure member, in the operative position, cooperates with said drivenmember for feeding web material at a rate in excess of that at whichsaid web advancing means can advance web material, so as to ease tensionin web material moving in the forward direction along the web pathbetween said driven and pressure members and said advancing means; meansfor sensing tension in web material moving in the forward directionalong the web path between said driven and pressure members and said webadvancing means; means for connecting said pressure member and said webtension sensing means for moving said pressure member from the idleposition to the operative position, in response to sensing a giventension in web material moving in the forward direction along the webpath between said driven and pressure members and said web advancingmeans, and for allowing said pressure member to return to the idleposition after tension in the same material has eased; and meanscooperating with said connecting means for preventing a connectionbetween said pressure member and said web tension sensing means as webmaterial is moved in the reverse direction along the web path, therebyto permit said pressure member to remain in the idle position.
 3. Thecombination as recited in claim 2, wherein said web advancing meansinitially serves to advance a leading end portion of web material in theforward direction onto a rotatably supported core member to which theleading web end portion can be snubbed and about which web material canbe wound, and wherein the combination further comprises: meansenergizable for holding said pressure member in the operative position,and deenergizable for allowing said pressure member to return to theidle position; and means actuatable in response to the leading web endportion snubbing to the core member for deenergizing said pressuremember holding means.
 4. The combination as recited in claim 2, whereinsaid pressure member is a pressure roller, and wherein said pressuremember supporting means supports said pressure roller for movementtoward and away from said driven member respectively between theoperative and idle positions and locates said pressure roller in saidweb handling apparatus such that web material moving between said drivenmember and said pressure roller is partially wrapped about said pressureroller for urging said pressure roller to move away from said drivenmember as tension in the same material increases.
 5. In a web handlingapparatus of the kind for moving web material in forward and reversedirections along a web path and under varying degrees of web tension,the combination comprising: means for drawing web material in theforward direction along the web path; a driven member against whichsuccessive portions of web material can be pressed for feeding webmaterial in the forward direction along the web path toward said webdrawing means; a presSure member; means supporting said pressure memberfor movement to an operative position in which said pressure member isdisposed to cooperate with said driven member for feeding web materialby pressing successive portions of web material against said drivenmember, and normally locating said pressure member in an idle positionin which said pressure member is disposed with respect to said drivenmember for permitting generally free movement of web materialtherebetween; means for driving said driven member with sufficient speedsuch that said pressure member, in the operative position, cooperateswith said driven member for feeding web material at a rate in excess ofthat at which said web drawing means can draw web material, so as toease tension in web material moving in the forward direction betweensaid driven and pressure members and said web drawing means; a web guidemember disposed with respect to said web drawing means and said drivenand pressure members for guiding web material such that a sufficienttensioning of web material moving in the forward direction between saiddriven and pressure members and said drawing means causes the samematerial to foreshorten in length and apply a web force against saidguide member; means supporting said web guide member for movement from afirst web guiding position to a second web guiding position in responseto web material applying a given force against said guide member; meansfor urging said web guide member from the second web guiding position tothe first web guiding position with an urging force which is less thanthe given force required to move said guide member from the first webguiding position to the second web guiding position; means forconnecting said pressure member and said web guide member such thatmovement of said guide member from the first web guiding position to thesecond web guiding position causes movement of said pressure member fromthe idle position to the operative position, and allowing said pressuremember to return to the idle position after tension has eased in webmaterial moving in the forward direction between said driven andpressure members and said web drawing means; and means cooperating withsaid connecting means for preventing a connection between said pressuremember and said web guide member as web material is moved in the reversedirection along the web path thereby to permit said pressure member toremain in the idle position.
 6. The combination as recited in claim 5,wherein said web drawing means includes means for continuously movingweb material, therepast, in the forward direction at a substantiallyconstant rate.
 7. The combination as recited in claim 6, wherein saidcontinuous web moving means includes a driven roller against whichsuccessive portions of web material can be pressed for moving webmaterial, therepast, in the forward direction, means for rotating saiddriven roller at a substantially constant speed, a pressure roller,means supporting said pressure roller for movement toward and away fromsaid driven roller and such that web material moving between said drivenand pressure rollers applies a web force against said pressure rollerfor urging said pressure roller to move away from said driven roller,and means for urging said pressure roller to press web material againstsaid driven roller with an urging force which is greater than a webforce applied against said pressure roller as web material is moved inthe forward direction between said driven and pressure rollers and whichis less than a web force applied against said pressure roller as webmaterial is moved in the reverse direction between said driven andpressure rollers.
 8. The combination as recited in claim 5, wherein saidweb drawing means and said driven and pressure members serve to draw webmaterial off a rotatably supported core member about which a web supplyroll is wound and to which a trailing web end portion is anchored,wherein said web guide Member supporting means supports said web guidemember for movement from the second web guiding position to a third webguiding position in the event that all but the trailing web end portionis drawn off the core member and web material moving in the forwarddirection between the core member and said web drawing meansforeshortens in length and applies a greater force against said guidemember than that required to move said guide member from the first webguiding position to the second web guiding position, wherein saidconnecting means includes motion transmitting means movable toconnecting and disconnecting positions respectively in which said motiontransmitting means connects and cannot connect said pressure and webguide members in motion transmitting relation, and wherein saidconnection preventing means includes means actuatable in response tomovement of said web guide member to the third web guiding position formoving said motion transmitting means to the disconnecting position. 9.The combination as recited in claim 8, further comprising: meansactuatable in response to movement of said web guide member to the thirdweb guiding position for initiating movement of web material in thereverse direction along the web path.
 10. The combination as recited inclaim 8, wherein said pressure member supporting means includes apressure member support arm which is pivotally mounted for moving saidpressure member toward and away from said driven member respectivelybetween the operative and idle positions, wherein said web guide membersupporting means includes a web guide member support arm which ispivotally mounted for moving said web guide member between the first,second and third web guiding positions, wherein said motion transmittingmeans includes a lever having opposite end portions and a fulcrumlocated therebetween such that said lever end portions and said pressureand web guide member support arms are movable respectively into motiontransmitting relation to cause movement of said pressure member from theidle position to the operative position as said web guide member ismoved from the first web guiding position to the second web guidingposition, and wherein said means for moving said motion transmittingmeans to the disconnecting position includes means for separating one ofsaid lever end portions and one of said pressure and web guide membersupport arms for preventing movement of said end portions and saidsupport arms into motion transmitting relation.
 11. The combination asrecited in claim 5, wherein said pressure member supporting meansincludes a pressure member support arm which is pivotally mounted formoving said pressure member toward and away from said driven memberrespectively between the operative and idle positions, wherein said webguide member supporting means includes a web guide member support armwhich is pivotally mounted for moving said web guide member between thefirst and second web guiding positions, wherein said connecting meansincludes a lever having opposite end portions and a fulcrum locatedtherebetween such that said lever end portions and said pressure and webguide member support arms are movable respectively into motiontransmitting relation to cause movement of said pressure member from theidle position to the operative position as said web guide member ismoved from the first web guiding position to the second web guidingposition, and wherein said connection preventing means includes meansfor separating one of said lever end portions and one of said pressureand web guide member support arms for preventing movement of said endportions and said support arms into motion transmitting relation.
 12. Animproved web handling apparatus of the kind (a) wherein there isprovided a driven member against which successive portions of webmaterial can be pressed for feeding web material, (b) wherein there isprovided a pressure member normally located in an idle position in whichsaid pressure member is dispOsed with respect to said driven member forpermitting generally free movement of web material therebetweeen, andmovable from the idle position to an operative position in which saidpressure member is disposed to cooperate with said driven member forfeeding web material by pressing successive portions of web materialagainst said driven member, (c) wherein there is provided a web guidemember disposed with respect to said driven member and said pressuremember such that a sufficient tensioning of web material extendingbetween said driven and pressure members and said guide member causesthe same material to foreshorten in length and apply a web force againstsaid guide member, and movable from a first web guiding position to asecond web guiding position in response to web material applying a givenforce against said guide member, (d) wherein there is provided means forconnecting said pressure member and said web guide member such thatmovement of said guide member from the first web guiding position to thesecond web guiding position causes movement of said pressure member fromthe idle position to the operative position, and wherein the improvementcomprises: said connecting means including a lever having opposite endportions and a fulcrum located therebetween, said lever fulcrum disposedwith respect to said pressure member and said web guide member such thatsaid lever end portions and said pressure and web guide members aremovable respectively into motion transmitting relation to cause movementof said pressure member from the idle position to the operative positionas said web guide member is moved from the first web guiding position tothe second web guiding position; and means for separating one of saidlever end portions and one of said pressure and web guide members forpreventing movement of said lever end portions and said pressure and webguide members into motion transmitting relation.
 13. The improvement asrecited in claim 12, wherein said connecting means further includes aconnecting member coupled to said web guide member for synchronousmovement therewith from the first web guiding position to the second webguiding position, said connecting member engageable with a particularone of said lever end portions as said web guide member is moved fromthe first web guiding position to the second web guiding position andmovable relative to said guide member for disengaging from theparticular one of said lever end portions, and wherein said separatingmeans includes means for disengaging said connecting member from theparticular one of said lever end portions and for holding saidconnecting member separated therefrom.
 14. The improvement as recited inclaim 13, wherein another one of said lever end portions is flexiblymovable.
 15. Film projection apparatus for moving film in forward andreverse directions, said apparatus comprising: means for supporting afilm supply; a film take-up; a film gate; means defining a path for filmfrom said film supply supporting means through said film gate to saidfilm take-up; means located with respect to the film path between saidfilm gate and said film take-up for advancing film in the forwarddirection through said gate and along the path at a first rate;actuatable film feeding means located with respect to the film pathbetween said film supply and said film gate, said film feeding means,when actuated, assuming a feeding mode in which said feeding means iseffective for feeding film in the forward direction along the pathtoward said gate at a second rate greater than the first rate, and saidfilm feeding means, when not actuated, assuming a non-feeding mode inwhich said feeding means is ineffective for feeding film along the path;film tension sensing means located with respect to a portion of the filmpath between said film feeding means and said film gate for sensingtension in film in such portion of the path; means for connecting saidfilm feeding Means and said film tension sensing means for actuatingsaid film feeding means to assume the feeding mode, in response to saidtension sensing means detecting a particular magnitude of tension infilm in such portion of the film path, and for allowing said feedingmeans to assume the non-feeding mode after tension in the same film haseased; means for moving film in the reverse direction along the filmpath; and means cooperating with said connecting means for preventing aconnection between said film feeding means and said film tension sensingmeans during movement of film in the reverse direction along the filmpath, thereby to permit said feeding means to remain in the non-feedingmode.
 16. Film projection apparatus as recited in claim 15, wherein thefilm path includes a plurality of bends between said film supplysupporting means and said film take-up, and wherein: said film feedingmeans includes a driven roller located at one side of the film path anda pressure roller located at the other side of the path, and a supportarm mounting said pressure roller for movement toward and away from saiddriven roller; said film tension sensing means includes a guide rollersupport arm, means mounting said guide roller support arm for pivotalmovement between first and second positions, a guide roller mounted onsaid guide roller support arm and movable with said guide roller supportarm between first and second film guiding positions, said guide rollerbeing located along the film path at the one bend in the path and thefilm being contactable with said guide roller as the film travels alongthe path so that said guide roller is urged from its first guidingposition toward its second guiding position in response to an increasein tension in film contacting said guide roller, thereby urging saidguide roller support arm from its first position toward its secondposition; and said connecting means includes a motion transmittinglever, means mounting said lever for pivotal movement into contact withsaid pressure roller support arm of said film feeding means foreffecting movement of said pressure roller carried by said pressureroller support arm toward said driven roller, a connecting fingerpivotally mounted on said guide roller support arm for movement between(1) a first position wherein a portion of said finger is positioned forengagement with said motion transmitting lever in response to movementof said guide roller support arm from its first position toward itssecond position under the influence of tension in film as sensed by saidguide roller so that such movement of the guide roller support arm caneffect movement of said motion transmitting lever to cause said pressureroller carried by said pressure roller support arm to be moved towardsaid driven roller in response to an increase in film tension, and (2) asecond position wherein said portion of said connecting finger islocated with respect to said motion transmitting lever so that saidfinger is ineffective to move said motion transmitting lever or saidpressure roller support arm in response to movement of said guide rollersupport arm from its first position toward its second position inresponse to an increase in film tension ss sensed by said guide roller.17. Film projection apparatus as recited in claim 16, wherein saidconnecting means further includes means urging said guide roller supportarm and said finger toward their respective first positions, and saidfilm projection apparatus further comprises a separating lever, meansmounting said separating lever for movement between (1) a first positionwherein said separating lever is located with respect to said finger forpermitting movement of said finger to its first position and (2) asecond position wherein said separating lever holds said finger in itssecond position against said urging means, and means for moving saidseparating lever between its first and second positions.
 18. Filmprojection appaRatus as recited in claim 17, wherein said means formoving said separating lever includes a spring connected to saidseparating lever for urging said separating lever to its first position,a solenoid coupled to said separating lever and effective when energizedto move said separating lever to its second position, and means forenergizing said solenoid.
 19. Film projection apparatus comprising:means for supporting a film supply; a film take-up; a film gate locatedbetween said film supply supporting means and said film take-up; meansdefining a path for film from said film supply supporting means throughsaid film gate to said film take-up, the film path including at leastone bend; means located along the film path between said film gate andsaid film take-up for advancing film through said gate and along thepath; actuatable film feeding means located along the film path betweensaid film supply and said film gate, said film feeding means including adriven roller located at one side of the film path and a pressure rollerlocated at the other side of the path, a support arm mounting saidpressure roller for movement toward said driven roller when said filmfeeding means is actuated, and away from said driven roller when saidfeeding means is not actuated, whereby said film feeding means, whenactuated, is effective for feeding film along the film path toward saidfilm gate, and said film feeding means, when not actuated, beingineffective for feeding film along the path; film tension sensing meanslocated along a portion of the film path between said film feeding meansand said film gate for sensing tension in film in such portion of thepath, said film tension sensing means including a guide roller supportarm, means mounting said guide roller support arm for pivotal movementbetween first and second positions, a guide roller mounted on said guideroller support arm and movable with said guide roller support armbetween first and second film guiding positions, said guide roller beinglocated along the film path at the one bend in the path and the filmbeing contactable with said guide roller as the film travels along thepath so that said guide roller is urged from its first guiding positiontoward its second guiding position in response to an increase in tensionin film contacting said guide roller, thereby urging said guide rollersupport arm from its first position toward its second position; andmeans for actuating said film feeding means in response to said filmtension sensing means sensing a particular magnitude of tension in filmin such portion of the film path, said actuating means including amotion transmitting lever, means mounting said lever for pivotalmovement into contact with said pressure roller support arm of said filmfeeding means for effecting movement of said pressure roller carried bysaid pressure roller support arm toward said driven roller, a connectingfinger carried by said guide roller support arm for movement therewithto a position wherein a portion of said finger is engageable with saidmotion transmitting lever in response to movement of said guide rollersupport arm from its first position toward its second position under theinfluence of tension in film as sensed by said guide roller so that suchmovement of said guide roller support arm can effect movement of saidmotion transmitting lever to cause said pressure roller carried by saidpressure roller support arm to be moved toward said driven roller inresponse to an increase film tension.